From the related art, it is generally known to mount rotor blades on a rotor in the axial direction of the rotor. To this end, a blade root of the blade is inserted into a groove provided in the rotor that extends in the axial direction of the rotor. The blade must be secured radially and axially relative to the rotor axis, in order to limit, respectively prevent a shaking, respectively vibratory movement of the blades, in particular upon start-up of the turbine engine. Such a shaking, respectively vibratory movement can cause surface damage to the rotor and/or to the blades, thereby shortening the service life of the turbine engine and degrading the efficiency during operation.
The German Patent DE 44 30 636 C2 describes a turbine engine having a blade and an axial groove in the rotor. The blade has a blade root in the shape of a fir tree. The blade root of the blade is inserted into the correspondingly shaped axial groove. The configuration of the blade root allows the blade to be radially secured relative to the rotor axis. A securing plate is provided in the axial groove between the blade root and the rotor. At the ends thereof, the securing plate has folding tabs for securing the blades in the axial direction. In the cross section normal to the axis, the securing plate has a rounded shape.
Such securing plates are known from U.S. Patent Application 2004/076523 A1 and European Patent Application EP 2 009 245 A1. In the figures, each of these has two radii, between which a concave portion is disposed that cannot come into contact with the groove.
A disadvantage associated with the known securing element is that the area of contact between the securing plate and the groove is small. Thus, a groove wall and/or a securing plate can become damaged when the force transmitted by the blade and the securing plate to the groove wall becomes substantial. A force of this kind can arise, for example, when a vibrating blade strikes against the groove wall.